Chilled roll



Patented Feb. 20, 1934 1,948,243 CHILLED ROLL William H. Seaman, Hammond, Ind.

N0 Drawing. Application May 3, 1930 Serial No. 449,686

11 Claims. (01. s0 5s The present invention relates in general to a novel alloy of iron for use in a chilled cast iron roll employed for rolling metal articles and in particular to a high carbon cast iron alloy chilled roll having a chill or a definite chill as it is often called.

One of the objects of the present invention is to provide an alloy iron of such character that hardness of the working depth may be varied to suit the conditions under which it is adapted to be used.

Another object is to provide a novel alloy of iron of such character that it may be substituted for forged steel.

Another object is to provide an iron alloy that is suitable for casting into chilled rolls of uniform characteristics throughout the depth of the chill.

Another object is. to provide an alloy of this character in which the hardness and depth of the chill may be controlled by modifying the constituents of the alloys in a predetermined manner.

A further object is to provide a novel process of making a cast iron alloy in which the hardness and depth of the chill may be varied as desired by varying the constituent elements according to a definite rule.

There are other objects of my invention which together with the foregoing will be described in the detailed specification which is to follow:

Various forms of iron alloys have been proposed heretofore and have satisfactorily functioned where intended but the cnstituent members of the alloy have been chosen haphazardly and have largely followed a rule of thumb. Furthermore, in their use in the making of cast chilled rolls the characteristics of the metal vary to a large extent throughout the depth 01 the chill. Again it has been impossible to obtain a cast iron roll which would be of sufficient hardness to do certain work requiring rolls of a sclerescopic hardness of 90 to 100. In this instance, it has been necessary to employ case hardened forged steel rolls which are exceedingly high priced and difficult to make.

My improved alloy eliminates all these disadvantages heretofore encountered. I have found that it is desirable to have the carbon contentof the alloy as high as possible. It is also necessary to have a high nickel content to secure the required hardness with chromium present to control the chill depth. I have found it desirable however, to have a very low chromium content in order to secure proper balance between the rolls.

gray iron body of the roll and its chill working depth and also to secure uniformity of texture of the chill throughout its depth.

These factors enable me to obtain an alloy having a uniform hardness throughout the depth of the chill and to control its depth and its balance with the gray iron in a roll which has been impossible to secure heretofore. Of course, manganese, silicon, sulphur and phosphorus are also present and vary in the alloys desired. However, the above discloses its salient characteristics and the fundamental ingredients that it is mainly necessary to control.

Below is a table of'the composition of rolls to obtain the sclerescopic hardnesses shown on the left:-

T. 0 Mn Si S P Cr Ni to to to to to to to 80 to 90 3. 15 15 25 115 l8 25 3.00

to to to to to to to 90 to 100 3. 25 15 l5 120 .18 25 4. 00

to to to to to to It will be seen that the chromium content forms a small proportion, for example about 10% of the nickel. That the total carbon may be generally increased from 2.60 to 3.85 in direct proportion to hardness desired though in the examples givenit goes to 3.25. The carbon tends to control the hardness. The nickel varies directly proportionate to the degree of hardness and gives toughness. The low manganese and silicon ensure the definite chill notwithstanding the high carbon and nickel. The sulphur varies in direct proportion while the phosphorus content remains more or less constant between limits given. These constituents in the proportions indicated give highly important results in chilled The alloy is made in the usual manner and cast in chilled molds in the same mechanical fashionas ordinary chilled rolls. The alloys give a sclerescopic hardness throughout the chill depth of from '70 to 100. The rolls having a sclerescopic hardness of from '70 to 80 are mainly used for hot rolling in sheets and plates. Where the sclerescopic hardness of the roll is increased to the roll is ordinarily employed in the rolling of sheet bar, strip, etc., also copper and brass. Rolls having a sclerescopic hardness from 85 to 100 are employed for cold rolling. It has been necessary heretofore in the rolling of these materials to employ a case hardened forged steel roll, which in addition to being exceedingly difiicult to make is short lived. The cost of these rolls is very high.

The alloys set forth above are very advantageous when employed in chilled iron alloy rolls, for the reason that the chill depth is of substantially uniform hardness throughout and the union between it and the gray iron core is close, resulting in a tough, resilient and durable roll suitable for the use required throughout the chill depth.

The alloys having a sclerescopic hardness from to when cast in a chilled mold are advantageously employed as before indicated for hot rolling and in this use are much longer lived, performing better work of uniform character throughout their life.

It will be seen that I have invented a novel method or process of making an iron alloy suitable for chilled rolls in which the sclerescopic hardness of the chill may be predetermined to meet the requirements of the particular work for which it is to be used, the hardness being increased as the carbon and nickel are increased and the silicon and manganese being decreased as the carbon and nickel are increased, so as to offset or balance the chill destroying tendency of the increased carbon and nickel.

While I have disclosed one method of making my improved alloy and several specific alloys of predetermined sclerescopic hardness, it will be understood that my invention may be variously changed and modified as shown in the appended claims.

I claim:-

1. A high carbon chilled iron alloy roll containing a small amount of silicon, chromium and manganese to ensure a definite chill, said amounts running from about .15 to about .65 silicon and from about .15 to about .27 manganese and from about .20 to about .50 chromium, said roll also containing a substantial quantity of nickel to secure toughness of said chill, said nickel running from about 2.50 to about 5.0.

2. A chilled iron alloy roll containing a small amount of silicon, chromium and manganese to ensure a definite chill, said amounts running from about .55 to about .65 silicon and from about .24 to about .27 manganese and from about .20 to about .30 chromium, said roll also containing substantial quantities of carbon and nickel to secure hardness of said chill, said carbon running from about 3.05 to about 3.15 and said nickel running from about 2.50 to about 3.0.

3. A chilled iron alloy roll containing certain ingredients to secure a definite chill, to-wit, silicon from about .15% toabout .65%, manganese from about .15% to about 27% and chromium from about .20% to about .50% and also containing carbon from about 2.65% to about 3.85% and nickel from about 2.50% to about 5.0% to secure hardness and toughness of said chill.-

4. A chilled iron alloy roll containing certain ingredients to secure a definite chill, to-wit, silicon from about 55% to about .65%, manganese from about 24% to about 27%, and chromium from about 20% to about 30%, and also containing carbon from about 3.05% to about 3.15%, and

nickel from about 2.5% to about 3.0% to secure hardness and toughness of said chill.

5. A high carbon chilled iron alloy roll having a definite chill and containing a small amount of silicon to ensure a definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the silicon being not to exceed .65 and being in such small quantity as to oifset or compensate the chill destroying or reducing effect of the large amount of nickel.

6. A high carbon chilled iron alloy roll containing a small amount of chromium to ensure the definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the chromium being not to exceeed .35 and being in such small quantity as to ensure the definite chill-notwithstanding the substantial quantity of nickel.

7. A high carbon chilled iron alloy roll containing a small amount of manganese to ensure the definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the manganese being not to exceed .27 and being of such small quantity as to ensure the definite chill notwithstanding the substantial quantity of nickel.

8. A high carbon chilled iron alloy roll containing small amsunts of silicon and chromium to ensure a definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the silicon being not to exceed .65 and chromium not to exceed .35 and both being in such small quantities as to ensure the definite chill notwithstanding the substantial quantity of nickel.

9. A high carbon chilled iron alloy roll containing small amounts of, silicon and manganese to ensure a definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the silicon being not to exceed .65 and manganese being not to exceed .27 and both being in such small quantities as to ensure the definite chill notwithstanding the substantial quantity of nickel.

10. A high carbon chilled iron alloy containing small amounts of chromium and manganese to ensure a definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the chromium being not to exceed .35 and the manganese being not to exceed .27 and both being in such small quantities as to ensure the definite chill notwithstanding the substantial quantity of nickel.

11. A high carbon chilled iron alloy roll containing small amounts of silicon and chromium and manganese to ensure a definite chill and also containing a substantial quantity of nickel to secure toughness of said chill, the silicon being not to exceed .65, the chromium being not to exceed .35 and the manganese being not to exceed .27 and all being in such small quantities as to ensure the definite chill notwithstanding the substantial quantity of nickel.

WILLIAM H. SEAMAN. 

